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Warfarin supratherapeutic INR — USMLE Step 3 MCQ

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HardInternal Medicine (chronic management)Warfarin supratherapeutic INRUSMLE Step 3

A 75-year-old man taking warfarin for atrial fibrillation has INR 5.4 on routine monitoring. He has no bleeding, normal vital signs, and stable hemoglobin. He recently completed trimethoprim-sulfamethoxazole. Which of the following would you recommend at the follow-up visit?

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Reveal the answer and explanation

Correct answer: D — Hold warfarin temporarily and monitor INR closely

Supratherapeutic INR without bleeding is managed by holding warfarin and monitoring, with vitamin K reserved for higher-risk situations.

Reference: CHEST antithrombotic therapy guidance: https://journal.chestnet.org/